Method and means for manufacture of paper



I Oct; 11, 1932. R. s; VONIHAZMBURGI" 1,881,985

METHOD AND MEANS FOR MANUFACTURE OF PAPER I Filed April 6, 1951 I I I .Patentecl Oct. 11, 1932 UNITED 1 STATES PATENT OFFICE p .ROMULUS S. VON HAZMBURG, OF CHESTER, PENNSYLVANIA, ASSIGNOR 'ro SCOTT PAPER COMPANY, A CORPORATION OF PENNSYLVANIA METHOD AND MEANS FOR Application filed April 6,

My invention embodies method and means for eliminating the coagulating or grouping of impurities from the paper stock at or before the time it is delivered to the wire of the 5 paper making machine, so that their actual presence is assured in such form as will prevent them operating to deface or clog the wire and thus cause the paper produced to be defective by reason of the resulting presence of holes at intervals apart formed through the body of the paper Web.

All paper pulps contain more or less resinous material, some of which gives con: siderable trouble in paper making. This trouble is commonly due to the presence of pitch in the pulp. This; resinous material or pitch is originally a constituent of wood and is associated in the fibers of the pulp. The resinous or pitch materialis separated from the fibers by beating, jordaning, pressing or other mechanical process to which the fibers are subjected during paper stock making. The pitch separates out of the pulp as a milky suspension in the white water and may -be of varying degrees of sub-division, and

moreover behaves as a typical colloidal solu-v tion. During the processing of the fiber, the colloidal solution of pitch takes on a negative charge which prevents the minute particles of resinous material from adhering to the fiber. Due to the constant mixing, however, this'colloidal solution of pitch coagulates into larger particles which can then be,

- .noticed as adhering lumps or splotches on the wire, felts and press rolls, of the Fourdrinier, causing them to operate defectively' in the other wise normal operation of the paper making machines. I

' A typical colloidal solution of a finely suspended solid in a fluid bears an'electrical charge. Such solutions are stable until something neutralizes'the charge, causing a precipitation or flocculation of this suspended material in the solution. There are several Ways by which this effect may be brought about; one is chemically performed by adding a colloidal solution having an opposite electrical charge, and another is by causing the solution to be brought into contact with grids or plates immersed therein,

MANUFACTURE or PAPER 1981. Serial in. 580,875.

said solution having a static potential, as pre ferred.

I have found by experiment that when white water is subjected to a static potential, the milky suspension is speedily flocculated, leaving a clear supernatent liquid; and that the desired result is secured by the employment of relatively high voltages in a shorter time; and while I do not limit myself to any particular voltages, I have found excellent results to be obtained with the use of 125 volts.

I have also determined that by the em ployment of terminal plates immersed in a circulating mass of a paper pulp, and said plates alternately positively and negatively charged with an electric current, the effect upon the pulp determined at the beginning and at the ending of the electric treatment of the pulp indicated that very little of the pitch separated from the fiber of the pulp; whereas in tests made upon the pulp without the employment of the electric charge, a materially larger amount of the pitch was beaten out or separated from the pulp and which by coagulation, increases into larger particles or masses which separate from the pulp and become deposited or lodged upon the wire, felts and other parts of the paper making machine, with the result that the paper'product as made will contain more or less holes or defects in the web prior to passing to the driers.

The abilty to eliminate the cause of these defects in the finished'product and to prevent recurrence in anobjectionable degree is far reaching because otherwise the defects due; to the soiling of the 'wire by the pitch deposits will continually repeat themselves with each revolution of the wire apronand will gradually increase the number of'defects per square yard'of the paper Web produ c v This defective operation is more especially due to the fact that when the particles, lumps or splotchesof colloidal substances adhere to the surface of the wire apron oflthe'Fourdrinier,.said deposits, to the extent of their presence, cause the paper to .be'formed in the web with apertures or holes of various; 1

shapes, these defects being more apparent I making machine, or in the beater, as preferred; and that the use of higher voltages produces the desired neutralizing effect in a shorter time. By way of example, I have further foundthat a voltage of 125 volts gives desirable results. For the purpose of illustrating my inven' tion, I have shown in the accompanying drawing the embodiment thereof which. is at present preferred by me, since the same is in form to give satisfactory andre liable results, but it is to be understood that the several instrumentalities of which my invention consists can be variously arranged and organized and that my invention is not limited to the precise arrangement and organization of the instrumentalities/herein shown and described.

Byway of illustration and not as a limitation, I have shown in the drawing, a head box Anof a paper making machine provided with grids br plates B and C, respectively charged with opposite polarities through the V mediationof any suitable source of electric current, preferably from a continuous current dynamo D and circuits E and F therefrom and respectively connected to and energizing the grids or plates. G represents the breast roll and-H the wire of a Fourdrinier equipment of a paper making machine.

, Instead of neutralizing the polarity of the pitch solution in thepulp in the head box, the neutralizing may be performed. at any stage, as for example, in the beating engine, in the jordan, or the pressing operations, in which the wood fibers are subjected to preliminary or -preparatory treatment prior to "the actual making of the paper. It is also to Y be understood thatmy invention includes the treatment of a mix'furnished or formed of sulphite and ground wood.

I have described my improved method and means in that particularity which Ideem to ,be the best exposition of my invention, and

that which I prefer in commercial practice, but I do not restrict or confine myself to the minoror secondary details, as such are susceptible of modification,--which may be re-- sorted to as'a matter of mechanical skill and"- without a departure from the spirit of the invention.

I claim: 1. The herein described step in the manufactur'aof paper in web form which consists tric charge normally existing upon the pulpand thereafter forming the neutralized pulp int o paper in web form.

3. In paper making apparatus, the combination in a paper making machine including pulp supplying means, with means in the path of the paper pulp supplied to the machine for neutralizing the static charge upon the pulp.

4. In a paper making apparatus, the combination with aFourdrinier machine, of a head box, and means for supplying an electric charge to the head box for neutralizing the electric charge upon the paper pulp being supplied to the wire apron. w

5. The'invention stated in claim 4,.Wherein further, the neutralizing means comprises two grids respectivbly in contact with the paper pulp being supplied through said head box.

In testimony of which invention, I hereunto set my hand.

ROMULUS s. VON HAzMBUnfif 

